Code result
P0687
ECM/PCM Power Relay Control Circuit High
Moderate severity
What it means
ECM/PCM Power Relay Sense Circuit Open: the circuit is open. Likely a broken wire, disconnected connector, or failed component.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Main relay contacts faulty
highOne of the most commonly reported causes for this code — check this first.
Sense wire open
mediumA plausible cause — test and verify before replacing parts.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Related help
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